Condensing Gas Boiler

Condensing Boilers

Simply Smart Engineering. Simply Better Home Heating.

When it comes to home heating, it’s all about comfort, convenience and reliability. At Rinnai, we design products that let you experience all three. Our extensive line of Condensing Boilers provides efficient whole-home heating, water heating or both in one advanced system.

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Comforting warmth and soothing hot water. Delivered from one smart system.

Home and water heating. Keeping comfort coming.

Comfort means different things to different people. Whether it’s consistent heat throughout a home, pleasant humidity levels, or continuous hot water, our industry-leading line of Condensing Boilers keeps comfort coming with unparalleled performance.

Improve efficiency - increase comfort: Advanced smart system technology includes an outdoor reset sensor that continually adjusts to changing temperatures.

Hot water without interruption: Our E Series “combi” models have the BTU to deliver whole-house heating and domestic hot water priority for homes with one to two bathrooms without compromise.

Wide range of options: Because comfort is such a personal choice, we offer nine models to give your customers a wide range of quality options for both existing homes and new construction.

Waste not, pay not with superior efficiency.

Conventional heating systems waste energy with significant heat loss expelled into the atmosphere. Rinnai Condensing Gas Boilers are designed to recover heat energy that is discharged into the flue and return it to the heat exchanger for maximum efficiency.

Energy-smart performance: Thanks to advanced technology, our condensing boilers have one of the highest AFUEs (Annual Fuel Utilization Efficiency) in the industry.

Consistently comfortable heat: Our modulating gas valve detects small temperature changes and responds with incremental increases in BTU.

One complete system: Our Condensing Boilers ship with a factory-assembled low-loss header (excluding ES0C), integrated boiler pump, and pre-programmed outdoor reset sensors.

Efficient warmth: You will experience a consistent level of warmth throughout your home and a consistent level of savings throughout the year

Quicker installation: With multiple venting options you need for quicker installations and lower labor costs. With Rinnai, nothing goes to waste ... from the dollars spent on home and water heating to the time it takes to get a boiler up and running.

Enduring quality. Lasting peace of mind.

No one can predict the future, but the past is a good gauge of things to come. Rinnai’s 100 years of superior engineering, safety and quality inspire peace of mind that our boilers will stand the test of time.

The Rinnai tradition of building in quality at every level with a 12-year heat exchanger warranty* ensures many years of comfort and warmth. And our superior technical support for professionals along with durability testing means peace of mind and performance you can trust.

* See Owner’s Manual for complete warranty details.


Stainless steel heat exchanger: Our proprietary self-cleaning, down-fired stainless steel heat exchanger with industry-leading performance and durability.

OSS (one-side sealed) construction: Maintains integrity during heat exchanger expansion and contraction.

Factory-assembled low-loss header kit. By shipping the low-loss header kit with the unit, we save installation professionals time and money compared to closely spaced tees.

Integrated boiler pump: Our boiler pump eliminates the need to size the pump for the boiler loop and keeps a tight rein on energy usage.

Space to spare, no matter where.

When you’re raising the bar on condensing boiler performance and efficiency, reducing their space requirements vs. traditional boilers simply comes with the territory. Rinnai Condensing Boilers can be easily retrofitted in existing homes or installed in new construction.

The E Series “combi” model: Provides heating and hot water in one compact wall- mounted design.

The floor-standing Q Premier Series: Features a boiler and tank all in one, presenting a complete, fully-assembled space-saving solution.

Multiple venting options on all models: Allows for installation in a variety of locations.

Rinnai Condensing Boilers

Unparalleled comfort and efficiency for your home. That’s what you get with our range of economical, reliable and space-saving Rinnai Condensing Boilers. And while a boiler may not be a focal point in your home, its function is of the utmost importance. That’s why the way a Rinnai Condensing Boiler is built sets it apart from other available heating and hot-water options.

1 Gas-Air Mix

2 Combustion of Gas-Air Mix

3 Hot CH Water

4 Flue Gasses

5 Fan and Venturi Assembly

6 Upside-Down Ceramic Burner

7 Stainless Steel Pipes

8 Condensate Outlet



Perfect for replacement or new construction, these all- in-one floor-standing boilers deliver high-volume hot water and efficient home heating.

Benefits unique to Q Premier

  • An abundance of hot water: QP130 provides 211 gallons in the first hour, while the QP85 provides 141 gallons
  • Space-saving boiler saves more than five times the footprint of a traditional boiler and indirect tank system
  • Easy set-and-connect installation: multiple plumbing and venting options; comes fully-assembled with integrated connections for domestic hot-water recirculation lines, factory-installed low-loss header and expansion tank
  • Perfect for remodeling with zero-clearance installation design

* 141,000 output for domestic.

** Based on AHRI testing standard for indirect-fired water heaters.

*** Based on 90° rise.



Ideal for light-commercial applications or any home with a separate indirect hot-water source, our wall-mounted boilers free up valuable floor space—while maintaining maximum comfort in your home.

Benefits unique to Q Series

  • Energy-efficient home heating from four boiler models that have an optional 3-way diverter valve to simplify installations that have an indirect tank
  • Consistent temperature delivery via a thermostatic mixing valve in our combi heating/hot-water boiler (Q175C) with an onboard 6.6 gallon fully-insulated, indirect tank
  • Only use as much energy as needed with the fully modulating boiler pump that uses just the BTU needed to meet the immediate demand (maximum BTU input ranges from 85,000 to 205,000)
  • Installation flexibility allows venting up to a total of 200 feet (100 feet vertically and 100 feet horizontally)



Perfect for homes with 1 to 2 baths, E Series Combi Boilers ensure homeowners won’t have to sacrifice continuous hot water.

Benefits unique to E Series

  • Space-saving, wall-mounted design integrates boiler pump and heating expansion tank
  • Faster hot-water delivery with plate-warming feature
  • Continuous hot water due to domestic hot water priority
  • Increased efficiency designed to meet your home’s needs (maximum BTU heating input from 75,000 to 110,000)
  • Proven long-lasting durability from stainless steel domestic hot-water plate heat exchanger
  • The E50C is specifically designed for multifamily applications or smaller single-family homes with up to 1.5 baths with no secondary piping or closely spaced tees required†

†Not required if the pressure drop in any system loop(s) does not exceed 4.6 of head at 4.5 GPM flow rate.